Electric snap switch



Jan. 4, 1938. G. J. MEUER ELECTRIC SNAP SWITCH Filed Dec. 3, 1935 4 Sheets-Sheet l AW a Jan. 4, 1938. G. J. MEUER 2,104,206

ELECTRIC SNAP SWITCH Filed Dec. 3, 19:55 4 Sheets-Sheet 2 Jan. 4, 1938. MEUER 2,104,206

ELECTRI C SNAP?" SWITCH Filed Dec. 3, 1935 4Sheets-Sheet 5 Jan. 4, 1938. UE 2,104,206

ELECTRIC SNAP SWITCH Filed. Dec. 3, 1935 4 Sheets-Sheet 4 I I i A .m Q

Patented Jan. 4, 1938 UNITED STATES ELECTRIC SNAP SWITCH George J. Meuer, Milwaukee, Wis, assignor to Cutler-Hammer, Inc.,'Milwaukee, Wis., a corporation of Delaware Application December 3, 1935, Serial No. 52,676

20 Claims.

This invention relates to improvements in electric snap switches, and more particularly to electric snap switches of the rotary type.

A primary object of the invention is to provide a relatively small rotary snap switch of simple, efiicient and inexpensive construction.

Another object is to provide a rotary snap switch of the multiple-circuit controlling type which is of small size but of relatively high current carrying capacity.

Another object is to provide for use of a minimum number of diflerent but interchangeable parts to afford a maximum number of switches having different circuit controlling characteristics.

Another object is to provide a switch of the aforementioned character having a novel form of combined stationary contact and terminal members and a novel form of contactor for cooperation therewith.

Another object is to provide an improved and simplified form of snap switch mechanism.

Another object is to provide a switch of the aforementioned character having the parts so designed as to facilitate assembly thereof.

Another object is to provide novel means for supporting and insulating the stationary contact and terminal members of the switch.

Another object is to provide a molded insulating base member adapted for use with all or less than all of a group of switch parts to provide a switch having any one of a number of difierent circuit controlling characteristics.

Another and more specific object is to provide a novel form of rotary snap switch for multiple speed control of relatively small motors such as those used in food mixing devices and the like.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate a number of different embodiments of my invention which will now be described, it being understood that the embodiments illustrated are susceptible of modification in respect of certain details of construction and arrangement of the parts therethe fiber insulating plate being broken away.

(6i. Mil-4i) Fig. 3 is a side elevational view of the switch, portions thereof, including the insulating base, being cut away for purposes of illustration.

Fig. 4 is a vertical sectional view on the line ll of Fig. 2. 5

Fig. 5 is a fragmentary vertical sectional view on the line 5-5 of Fig. 4.

Figs. 6 and 7 are, respectively, bottom and top plan views ofthe molded insulating base of the switch.

Fig. 8 is a perspective view, in separated relation, of certain of the switch parts.

Fig. 9 is a perspective view, in separated relation, of one of the combined contact and terminal units.

Fig. 10 is a top plan view of a three-position rotary snap switch having a modified form of mounting means,--the manually operable knob or handle being omittedfor purposes of illustration.

Fig. 11 is a bottom plan view of the switch shown in Fig. 10, certain of the switch parts being omitted.

Fig. 12 is a side elevational view of a switch like that shown in Figs. 10 and 11, and illustrates the manner of mounting the same in concealed relation to a suitable housing or casing.

Fig. 13 is a fragmentary vertical sectional view oi the switch shown in Fig. 12 prior to attachment thereof to the housing or support.

Fig. 14 is a perspective view of the spring member shown in Fig. 12 which is employed to clamp the switch to a suitable support.

Fig. 15 is a bottom plan view of the insulating base having a modified arrangement of the ratchet-plate with respect thereto to provide a 35 three-position rotary snap switch, including an intermediate off position.

Fig. 16 is a view similar to Fig. 15, but showing certain of the movable parts of the switch in assembled relation, and showing the desired arrangement of the three combined contact and wiring terminal units.

Fig. 17 is a view similar to Fig. 15 but illustrating av further modified arrangement of the ratchet-plate to provide a rotary snap switch of the two-position, three-point type.

Fig. 18 is a view similar to Fig. 17, but showing certain of the movable parts of the switch in assembled relation, and showing the desired arrangement of the three combined contact and Wiring terminal units whereby two alternative on positions are provided.

Fig. 19 is a view similar to Fig. 18, but employing only two combinedcontact and wiring terminal units arranged as shown to provide a rotary snap switch having only one on position and one off position,it being understood that the ratchet plate employed in the switch of Fig. 19 may be identical with that shown in Fig. 17 and arranged in a like manner.

Figs. 20 and 21, are, respectively, bottom and top plan views of a modified form of insulating base to be employed in the production of a switch the bridging contactor of which is rotatable in either direction from any given position thereof,said switch having three on and two off positions.

Fig. 22 is a perspective view, in separated relation, of certain of the switch parts employed in conjunction with the base of Figs, 20 and 21.

Fig. 23 is a perspective view, in separated relation, of the metal and insulating top plates which may be employed with the base of Figs. 20 and 21, and

Fig. 24 is a fragmentary vertical sectional view of a switch of the character illustrated in Figs. 20 to 23.

Referring first to Figs. 1 to 9, inclusive, the numeral 25 designates a molded insulating base of approximately triangular contour.the base and apex portions of the triangle, however, being curved about a common center. Base 25, which is of relatively shallow depth or thickness is provided with a flat lower surface 26 and a substantially fiat upper surface 2'! parallel thereto,said upper surface 21, however, being provided with a pair of substantially cylindrical bosses or projections 28 and 29 (Fig. '7) for interlocking engagement with the walls of openings provided in the metal top plate 30 (Fig. 5) and the relatively thin fiber insulating plates 3| and 32 associated therewith to prevent relative rotary displacement of said parts.

The bottom surface 26 of base 25 is provided with a symmetrically located substantially circu-' lar recess 33, and said base is provided with a cylindrical passage 34 communicating centrally with said recess. The bottom wall of recess 33 is provided with an annular boss or projection 35 surrounding the passage 34, said boss having an inner offset or shoulder 36 (Fig. 6) to accommodate the correspondingly offset portion 31*- of a punched and stamped sheet metal ratchet-plate 31. Ratchet-plate 31 is shown in detail in Fig. 8 and the same is arranged Within recess 33 in the manner indicated in dotted lines in Fig. 6. Also formed integrally with the bottom wall of recess 33, and arranged in the plane of said annular boss 35 are five radially enlarged or segment-form bosses 38 to 42, inclusive, arranged in spaced relation to each other throughout an arc of approximately 225 degrees. Ratchet-plate 31 (Fig. 8) is provided with five integral radial projections or lugs 43 to 41, inclusive, which are adapted to overlie the aforementioned bosses 38 to 42, respectively, for a predetermined portion of the radial length of the latter. Bosses 38 to 42 are respectively provided with slight projections 38 and 42 (see Figs. 6 and 15) which underlie the outer ends of lugs 43 to 41 to prevent accidental downward bending or deforming of the latter after assembly of the switch parts. Bosses 38 to 42, might, of course, be otherwise formed to accomplish the result just mentioned.

Referring to Fig. 11, it will be noted that the ratchet plate 3'! is preferably initially provided with a sixth projection or lug 48. In the switch of Figs. 1 to 9, however, the lug 48 is not required nor desired, and accordingly the same is sheared off or otherwise removed, as indicated at 48 in Fig. 8. As will be apparent, the ratchet plate 31 of Figs. 1 to 9 is thus provided with a series of four equally spaced radial grooves 49, 50, 5| and 52 (Fig. 8),-each groove having a pair of parallel side walls for cooperative engagement thereof by a resiliently mounted stop lug 49 formed integrally with and extending at an angle from the main body portion of a metal member 4!), hereinafter more fully described.

Base 25 is provided at the large end thereof with a group of three radial notches 5|, 52 and 53 and at the smaller end thereof with a single radial notch 54 (Figs, 6 and 7), said notches, as shown, opening to the upper surface 21 of the base, and the opposite side walls of said notches having vertical grooves the upper ends of which likewise open to said surface 21 and the lower ends of which provide seats for the enlarged or shouldered portions of a corresponding number of combined resilient stationary contact and wiring terminal units which are insertable into said notches from the upper surface 21 of the base. One pair of said grooves is designated at 54, 54 in Fig. '7,it being understood that the other pairs of grooves are of like form and have similar functions.

The combined resilient contact and wiring terminal units are of like form, and one of the units is shown in detail in Fig. 9. Said unit comprises a refiexed contact element 55 preferably formed of bronze or a similar highly resilient metal or alloy. The lower end portion of element 55 is angled inwardly as shown and the side edge portions thereof are preferably bent or curved rearwardly, as shown at 55, to facilitate movement I of a contactor into engagement therewith. Element 55is bent or reflexed to provide the downwardly extending end portion 55 ,the latter being provided with shoulders 55, 55 adapted to seat within a set of grooves such as indicated at 54, 54 Fig. 7. Insertable upwardly between the reflexed ends of element 55 is a terminal plate 56 formed of any suitable metal such as brass,- plate 55 having shoulders 56, 56 formed thereon to also seat within grooves, such as 54, 54 when the complete unit is inserted downwardly from the upper surface 21 (Fig. 7) of base 25. Plate 56 has an opening formed therein by inward extrusion of a flange 56, and said opening is tapped as shown at 56 to receive the shank of a binding screw 51,it being noted that contact element 55 is provided with an opening 55 to provide clearance for the shank of said screw. Moreover, element 55 is provided with a substan tially elliptical cut away portion or opening 55, said opening being adapted to facilitate bending of element 55 to the form illustrated, to increase the flexibility thereof, and to provide clearance for the aforementioned shank of the screw 51.

In practice the combined contact and terminal unit is assembled by threading the shank of screw 57 only a slight distance into opening 56 whereupon the unit may be inserted downwardly into one of the notches in base 25 from the upper surface 21 of the latter,the aforementioned pairs of shoulders 55, 55 and 56, 56 being adapted to seat jointly within the opposed grooves (such as 54, 54*) and against the bottom walls thereof, to provide for positioning of the upper end of the unit in a relation substantially flush with the upper surface 21 of said base. Base 25 (Fig. 6) is formed as indicated at 5N, 52, 53 and 54 to accommodate the shanks of the several screws 51, and when the several units are inserted into their respective notches in base 25, the screws 51 may be driven in to a greater distance than that aforementioned, whereby the units are temporarily held against separation from the base, as best illustrated in Fig. 4. If desired, of course, the contact and terminal units may be inserted into the base notches prior to attachment of the binding screws.

Upon assembly of the aforementioned units with respect to base 25, the insulating plates 32 and 3| and the metal plate 30 are laid in sequence over the upper surface 21 of the base,- the bosses 28 and 29 being accommodated by the alined openings in said plates, as best illustrated in Fig. 5, whereby the latter are restrained against rotation relatively to the base. Thereupon the reduced lower end 58 of an externally threaded hollow metal bushing 58 is inserted downwardly through alined openings in plates 38, 3| and 32, through the passage 34 in base 25, and through the opening 31 in ratchetplate 31 (see Fig. 8) and is upset over the offset portion 31 of the latter, as best illustrated at 58 in Fig. 4, whereby the several parts aforedescribed, including the combined contact and terminal units, are rigidly and permanently attached to base 25.

The peripheral wall of the opening 31 in ratchet-plate 31 is preferably notched, as indicated at 31 in Fig. 8, to assist in preventing rotation of bushing 58 with respect thereto after the .aforedescribed upsetting operation. Bushing 58 Fig. 4) for interlocking engagement with the side walls of the bushing groove 58 to insure a predetermined fixed position of said groove with respect to said top plate and the base 25 and ratchet plate 31. Any suitable form of indicating plate (such as is shown in dotted lines at 59 in Fig. '1) having an opening to accommodate bushing 58 and a lug to enter the groove 58 may be provided,--said indicating plate being provided with suitable legends corresponding with the off position and the first, second and third on positions of the switch. The operating knob or handle 68 of the switch is provided with an arrow 60 to cooperate with the legends aforementioned to indicate the particular position of the switch mechanism and/or the condition of the electric circuits to be controlled thereby.

It will be noted from Fig. 4 lug 3|] is sheared from a point spaced outwardly from the relatively large central openingin plate 36, wherefore said lug extends upwardly only a short distance into the groove 58, thus minimizing interference of lug 30 with full downward movement of the lower clamping nut 6| associated with bushing 58,a second or upper clamping nut 62 being likewise preferably provided. If a lug like 38 were sheared from a point coincident with the periphery of the relatively large central opening in top plate 38 it would be necessary to thereafter clip the lug to the length shown to avoid the aforementioned difiiculty,- or, as an alternative, it would be necessaryto substantially deepen the groove 58. The arrangement of lug 30 herein shown "and described therefore aifo-rds a much simpler solution of this particular problem.

The movable parts of the switch mechanism are constructed and arranged in the following manner: An actuating cam plate 63 is adapted to bear against and is rotatable with respect to the ratchet-plate 31, said plate 63 having two sets of double-inclined cam surfaces 63 and 63 arranged as extensions at diametrically opposite points in the periphery thereof. Said pairs of cam surfaces are arranged in downwardly offset relation to the main body of plate 63 and ratchet-plate 31 and the cam surfaces of said pairs converge downwardly from said ratchet-plate. Cam plate 63 is further provided at a peripheral point midway between the pairs of cam surfaces with a lug 63 the outer end portion 63 of which is bent upwardly at substantially a right angle wherefore the same is adapted to. clear the peripheral edge portion 31 of ratchet-plate 31 (Fig. 8) but is adapted to engage the edge or shoulder 43 provided by radial lug 43 on plate 31 to limit rotation of plate 63 in one direction and to engage the edge or shoulder 41 provided by radial lug 41 to limit rotation of plate 63 in the reverse direction. Plate 63 is provided with a central opening 63 of non-circular (preferably square) contour to slidably receive the spindle 64 of corresponding form in cross section, to provide for positive driving of plate 63 by said spindle.

A second, or actuated, cam plate 65 is likewise provided at diametrically opposite points in the periphery thereof with sets of downwardly converging double-inclined cam surfaces 65, 65 which are normally adapted to seat or nest against the sets of double-cam surfaces 63, 63, respectively. The inner edges of said doubleinclined cam surfaces 65*, 65* are separated from the main body of plate 65 as by means of arcuate slots or cut-outs 65, 65, whereby formation of said cam surfaces is facilitated. Plate 65 is provided centrally thereof with a circular opening 65 of sufficient size to afford rotary clearance between the same and the aforementioned spindle 64, whereas the lower flat surface 65 of plate 65 around-said opening 65 is adapted to form an abutment for one end of .a coiled compression spring 66 which surrounds said spindle,- the other end of spring 66 being adapted to abut a washer or plate 67 (see Figs. 4 and 5) which is rigidly attached to the lower end of the spindle, as by upsetting or riveting the reduced portion of said end over said washer as indicated at 64. The opposite end coils of spring 66 are preferably formed to lie in substantially horizontal planes (Figs. 4 and 5), and the spring ends are further flattened by grinding the same in planes at right angles to the length of the spring.

Plate 65 is provided at peripheral points midway between the sets of double-cam surfaces 65,

65 with arms or extensions 65, 65 bent downwardly at substantially right angles thereto,-said arms being adapted to abut or seat against the upper surface of a substantially circular insulating disk or plate 68; and said arms having reduced and forked or slotted extensions 65*, 65 adapted to penetrate suitable openings 68 68' provided in plate 68. The spaced portions of said extensions are further spread apart edgewise'over the lower surface of plate 68 (as best illustrated in Fig. 2), or otherwise bent over said surface to rigidly secure cam plate 65 and insulating plate 68 to each other. During assembly of plates 65 and 68 I interpose between the upper surface of the latter and the arm 65 the fiat base portion 49 of the aforementioned resilient metal member 49*, said base portion 49 having a. rectangular opening 48 to accommodate the extension 65 of said arm whereby member 49 is clamped in position. The main body portion of member 19 is bent to extend upwardly at an angle to the base portion 49 thereof and is provided with an opening 49 to provide clearance for both the spindle 64 and the spring 66. The vertically extending lug 49 on member 49 freely penetrates an opening 65 provided in cam plate 65 adjacent to the arm 65 on the latter.

When the cam plate 65 is in normal or nested position with respect to cam plate 63 said lug 49 of member 49* will extend upwardly into one or another of the notches 49, 50, P and 52 inclusive, provided in ratchet-plate 31, and said lug will engage either wall of the particular notch to prevent rotation of cam plate 65 and the insulating plate 68 attached thereto pending withdrawal of lug 49 from engagement with the notch wall. The arrangement of the parts is preferably such that upon rotation of spindle 64, and consequently of cam plate 63, through an arc of approximately 45 degrees, the cam plate 65, which is restrained against rotation by cooperative engagement of lug 49 with the walls of a notch in ratchet plate 31, is forced vertically downward to increase the degree of compression of spring 66 and to simultaneously eifect withdrawal of lug 49 from said notch. When cam plate 65 is thus freed from restraint the spring 66 will force the same to move with a snap action into nesting engagement with cam plate 63, such movement of cam plate 65 obviously comprising rotation thereof through the aforementioned arc of approximately 45 degrees.

During such rotation of cam plate 65 the same also moves vertically upwardly to the normal position thereof as illustrated in Figs. 3, 4 and 5, wherefore the resiliently mounted lug 49 is positively engaged with the next succeeding notch in ratchet-plate 31. The aforedescribed operation of the switch parts is the same regardless of the direction in which the spindle 64 is rotated,- except, of course, as rotation of the spindle in one direction or the other is limited by engagement of the upstanding lug 63 on cam plate 63 with one or the other of the stop shoulders 43 or M on ratchet-plate 31.

The insulating plate 68 is likewise provided with a central opening 68 to afford clearance for spindle 64 and spring 66, and the same is further provided with a pair of diametrically opposed relatively shallow peripheral notches 68 66, the line between notches 68 68 being arranged at substantially right angles to a diametric line extending through the aforementioned openings 68 68 in plate 68. Peripherally spaced from the notch 68 on opposite sides thereof by arcs or angles of approximately 45 degrees are the notches I58 and 68 The four notches just mentioned are alined with and respectively adapted to accommodate a portion of the thickness of the upwardly bent ends 69 69, 69 69 of the four arms 69 69 69 and 69 of a bridging contactor 69. Contactor 69 is adapted to seat flatwise against the lower surface of insulating plate 68, and the reduced portions 692 69 69 and 69 of the aforementioned ends are bent inwardly over the upper surface of plate 69 to rigidly and permanently secure said contactor to said plate (see Fig. 4).

As best illustrated in Fig. 2, the switch parts when assembled provide for cooperation of those portions of the bridging contactor associated with arms 69*, 69 and 69 with the single resilient stationary contact carried at the apex of the substantially triangular insulating base 25,whereas that portion of the bridging contactor associated with arm 69 is adapted for cooperation with the set of three resilient stationary contacts carried at the base of the triangle. The position of the bridging contactor 69 in Fig. 2, wherein the contactor portion associated with arm 69 is engaged with the single stationary contact and the contactor portion associated with arm 69 is engaged with the middle contact of the aforementioned group of three, may be assumed to provide for second or intermediate speed of a motor controlled by the switch. Upon counterclockwise movement of the bridging contactor (Fig. 2) through an angle of 45 degrees the contactor portion associated with arm 69 will be moved into engagement with the right hand contact of the set of three, and the contactor portion associated with arm 69 will be simultaneously moved into engagement with the aforementioned single contact. This may be assumed to provide for third or high-speed operation of the motor controlled by the switch.

Similarly, upon clockwise movement of the contactor 69 through an angle of 45 degrees from the position thereof illustrated in Fig. 2 the contactor portion associated with arm 69' will engage the left-hand contact of the group of three and the contactor portion associated with arm 69 will engage the single contact. This may be assumed to provide for first or slow speed operation of the controlled motor. Another clockwise movement of the contactor 69 through an angle of 45 degrees will effect disengagement of the contactor portion associated with arm 69 from the lefthand contact of the aforementioned group of three and disengagement of the contactor portion associated with arm 69 from the aforementioned single contact. This is the oil position of the switch. It is true that in the off position of the switch the contactor portion associated with arm 69 will engage the right-hand contact of the group of three, but no circuit will be completed because all. portions of the contactor are then disengaged from the single contact aforementioned.

As best illustrated in Fig. 4 the resilient portions of the four stationary contacts are extended a substantial distance below the lower surface of the insulating base 25. By this arrangement I am enabled to compensate or take care of the axial movement of the bridging con- I advantageous in that it provides for maintenance of the several contacting areas in clean and bright condition; whereas the rotary'snap movement of the contactor into and out of engagement with the stationary contacts likewise affords a wiping action therebetween.

Referring to Figs. 2, 4, and 9 it will be noted that I provide the terminal plates 56 with downwardly extending inwardly angled lugs 56 which overlie the resilient portions '55 of the contacts in the plane of the insulating plate 66 in the normal position of the latter (see Fig. 4). This arrangement provides for limiting inward displacement of the terminal plates due to pressure applied to the terminal screws 51 during wiring of the switch, wherefore excess bending or distortion of the reflexed upper end portions of the resilient contact elements is prevented. A predetermined degree of bias or pressure of the resilient portions 55 of the contacts against the periphery of insulating plate 68 is thus insured.

Also as will be apparentonly a very small degree of lateral movement of the resilient portions 55 of the contacts is effected as an incident to engaging and disengaging movement of the bridging contactor. This minimizes vibration of the resilient contact portions during circuit making and/or breaking operations of the switch, wherefore arcing and pitting of the contact surfaces is substantially eliminated and the useful life of the switch parts is greatly increased.

In assembling the spindle 64 with respect to the other switch parts (the knob 60 being removed), the spring 66 is telescoped over the upper end of the spindle, and the lower end of said spring seats against the aforementioned Washer 61; I prefer to likewise telescope over the spindle and the spring an annular insulating ring or Washer 10, the central opening 10 of which is of smaller size than the washer 61. The purpose of insulating washer 10 is to insure parallel positioning of the plate 68 during movement thereof axially of the spindle, and to assist in properly insulating the current carrying parts of the switch. The spindle 64 is inserted upwardly through the several switch parts until the spring which abuts the washer 61 and the cam plate 55 is compressed to a predetermined degree. A predetermined length'of the spindle 64 will then project upwardly beyond the upper end of bushing 58, and said spindle is provided with a groove 64 (Fig. 4) to receive an open sided washer H of known form, said washer being slightly resilient to require a press or snap fit thereof onto the spindle, whereby accidental separation of the washer is prevented. Washer H thus serves to restrain the spindle against downward displacement relatively to the bushing 58, whereby the aforementioned degree of compression of spring 66 is insured.

The knob 60, which is preferably molded from insulating material of the phenol-formaldehyde condensation type, such as that sold commercially under the trade name of Bakelite, is provided centrally thereof with a passage the lower end portion 60* of which is of square cross section to accommodate a portion of the upper end of spindle 64 whereby the spindle is constrained to rotate with the knob. Another portion 60 of said passage is of a size only sufficiently large to provide clearance for the shank I2 of a screw which takes into a tapped opening 64 in the upper end of spindle 64. A third portion 60 of said passage is preferably of circular cross section and of a size to accommodate the head l2 of said screw,-a split lock-washer 13 of known form being interposed between said screw head and the bottom wall of portion 60 to prevent accidental loosening of said screw. Said passage is further provided at its upper end with a countersink 60 into which a disk or plate 14 of celluloid or the like, of a color either like or contrasting with the color of knob 60, is inserted with a press fit in a relation substantially flush with the upper surface of the knob.

I prefer to make the metal top plate 30 and the insulating plate 32 of the same contour as the base 25, whereas the insulating plate 3|, which is otherwise of the same contour as said base, is provided with four integral lugs 3|, 3|, 3| and 3K, arranged as best shown in Fig. 1 and initially positioned in the plane of the main body of said plate 3l,said lugs being bendable downwardly (after wiring of the switch) to assist in properly insulating the wiring terminal screws. In installations where such lugs are not required or desired, they may be readily torn or out oh by hand without disturbing the other parts of the switch unit. Where said lugs are not desired in the switch as initially produced, a plate like 32 may be substituted for the plate 3|; or a single insulating plate twice as thick as the plate 32 may be employed.

While the switch illustrated in Figs. 1 to 9, inclusive, is particularly well adapted for multiple-speed control of a relatively small motor of the character employed in food mixers and the like, various other uses for the switch will at once suggest themselves to those skilled in the art.

In practice (see Fig. 6) I prefer to provide base 25 with a series of four integral bosses 25 25 25 and 25 which receive with a fairly snug fit the inner end portions of four of the radial notches provided in ratchet plate 31. Said bosses assist in restraining the ratchet plate against rotary displacement relatively. to base 25, and the same assist in strengthening the several lugs 43, 44, etc., to prevent distortion or bending thereof under the impact of the aforedescribed stop lug 49 The ends of said bosses are likewise arranged in the plane of the lower surface of ratchet plate 31 to thereby afiord a substantially complete circular bearing surface for the cam plate 63 aforedescribed.

Referring now to Figs. to 14, inclusive, wherein I have shown a rotary snap switch the contactor of which is movable from an extreme off position in sequence to two on positions, it

will be noted that I am able to employ most of the switch parts 'aforedescribed, and such like parts have been given corresponding numerals of reference. As heretofore pointed out, however, the radial lug 48 is allowed to remain (see Fig. 11), whereas in the switch of Figs. 1 to 9 lug 48 was removed. Due to the presence of lug 48 the shoulder 48 thereof cooperates with the shoulder 43 on lug 43 to limit the aforementioned lug 63 on cam plate 63 (Fig. 8) to movement through an arc of approximately 135 degrees. Also as shown in Fig. 11 the combined contact and wiring terminal unit is omitted from the radial notch 53in base 25. The movable parts of the switch mechanism (including knob 60, spindle 64, plate 68, contactor 69 and the cam plates, not shown) may be identical with the corresponding parts in the switch of Figs. 1 to 9.

Thus assuming assembly of the movable switch parts to the base of Fig. 11 in a manner similar to that illustrated in Fig. 2, it is to be understood that in the off position of the switch the single arm 69* of bridging contactor 69 will be positioned one notch (or 45 degrees) above the left-hand contact of the group of two, and the contact arm 69 of the group of three will be positioned one notch (or 45 degrees) to the right of the single contact. Upon counterclockwise snap movement of the contactor, with reference to Fig. 11, the single arm 69* of the contactor will engage the left-hand contact of the group of two, and the arm 69 of the contactor will simultaneously engage the aforementioned single contact. Upon further counterclockwise snap movement of the contactor the single arm 69 thereof will engage the right-hand contact of the group of two, and the middle arm 69 of the group of three will simultaneously engage the aforementioned single contact. Step-by-step movement of the bridging contactor in the reverse direction with a snap action may be effected by merely reversing the direction of rotation of the knob and spindle 64.

The mounting means for the switch of Figs. 10 to 14, preferably comprises a hollow metal bushing 15 the relatively large substantially cylindrical upper end portion of which is provided with a pair of parallel flat sides 15 and 15 to accommodate the indicating plate 16 having a correspondingly shaped opening formed therein to prevent relative rotation of said parts, said bushing having horizontal shoulders 15, 15 to prevent upward displacement of plate 16. Bushing 15 is provided with a portion 15 of reduced diameter to avoid interference with the lug 30*, which is a standard part of the metal top plate 30 (Fig. 13), although said lug performs no useful func tion in the switch of Figs. 10 to 14. The further reduced lower end 15 of said bushing penetrates the several parts illustrated in Fig. 13 and is upset over the ratchet plate 31, as indicated at 15 After the switch has been wired and the knob 60 has been attached thereto the same may be assembled by sliding the same laterally into a slot provided in the curved edge of a casing member 11,said slot being formed to interlock with the aforementioned fiat sides 15, 15 of the bushing to prevent rotation of the latter with respect to said casing section. Thereafter the spring clamping member 18 has its forked end 18 slid into a position straddling the reduced portion 15 of the bushing. Thereafter the end portion 19 of the casing is moved into overlapping relationship to the casing part 11, as shown at 19 in Fig. 12, said casing part 19 being likewise notched to accommodate a part of the bushing 15 whereby lateral displacement thereof is prevented. The inwardly curved end portion 19 of casing section 19 likewise engages the curved end portion 18 of clamping member 18 to prevent displacement of the latter. Casing sections 11 and 19 are bolted or otherwise rigidly attached to each other in any well known manner.

As shown in Fig. 12 the member 18 is compressed or tensioned to a predetermined degree in the assembled relation of the parts, whereby the switch mechanism is resiliently maintained in proper position. As illustrated in Figs. 12 and 13 the indicating plate 16 has high and low portions 16 and 16 to respectively accommodate the different contours of the casing parts 19 and 11,said plate 16 being curved in the manner best illustrated in Fig. 13 to conform to the curvature of said casing sections. The mounting means of Figs. 1 to 9 may of course be substituted for that of Figs. 10 to 14, and vice versa, during manufacture of the switches aforedescribed, as will be obvious.

In the switch of Figs. 15 and 16 either of the aforedescribed mounting means may be employed, whereas the switch parts are identical with those described in connection with Figs. 10 to 13, but a slightly diiferent arrangement of certain of said parts is effected. That is to say, the ratchet-plate 31 having lug 48 is employed, but said ratchetplate is displaced in a counterclockwise direction through a rotary angle of 45 degrees with respect to the arrangement illustrated in Fig. 11. Moreover, as shown in Fig. 16 only three combined contact and terminal units are employed (as in Fig. 11), but one of the group of two units is inserted into radial notch 51 and the other unit is inserted into radial notch 53,-the middle notch 52 of the group of three being left vacant. With all of the other switch parts arranged as aforedescribed, it will be apparent that in Figs. 15 and 16 I have provided a rotary snap switch having two extreme on positions and an intermediate oif position,the bridging contactor being limited by the means aforedescribed to rotary movement through a total are or angle of 90 degrees.

In the switch of Figs. 17 and 18 I employ substantially the same parts as in the switch of Figs. 15 and 16. However, in Figs. 17 and 18 the ratchet-plate 31 is displaced in a counterclockwise direction through a rotary angle of 45 degrees with respect to the arrangement illustrated in Figs. 15 and 16, and accordingly the ratchet plate 31 must be further notched or cut away to accommodate the stud or projection 25 For this reason the cam plate 63 (Fig. 8) will be limited to movement through a rotary angle of only 45 degrees,-the lug 63 on cam plate 63 being limited in one direction of rotary movement by engagement thereof with the edge or shoulder 43 on lug 43 of the ratchet-plate, and said lug 63 being limited in the other direction of rotary movement by engagement thereof with the shoulder "12 (Fig. 17) on the aforementioned boss 42. Therefore in Figs. 17 and 18 the radial notch 5| is left vacant and the group of two combined contact and terminal units are respectively positioned within radial notches 52 and 53 of base 25. Figs. 17 and 18 therefore illustrate a switch of the three-point type; that is to say, a switch having two alternative on positions with a single wiringterminal common to said on positions, no off position being provided.

' The switch of Fig. 19 is the same as that shown in Figs. 1'1 and 18, with the exception that only two combined contact and terminal units are employed,both of the radial notches 51 and 52 in base 25 being left vacant. Thus the switch is shown in off position in Fig. 19, whereas upon snap movement of the contactor in a counterclockwise direction through an angle of approximately 45 degrees the contactor portion associated with the single arm 69 is engaged with the contact portion 55 of the unit positioned in notch 53, and the contactor portion associated with arm 69 is simultaneously engaged with the contact portion of the unit positioned in notch 54. In Fig. 19 I have thus provided a rotary snap switch of the two-position, or on and off, type. It will be apparent to those skilled in the art that a switch of the character illustrated in Fig. 19 might be provided by employing a contactor comprising only the diametrically opposed arms 69 and 69 (with the contactdr arms 69 and 69 omitted), and with the combined contact and ter minal unit transposed from notch 53 to notch 52. With such an arrangement the peripheral notches in plate 68 which accommodate the bent end portions of the arms 68 and 69 would also preferably be omitted.

In the further modified form of switch illustrated in Figs. 20 to 24, inclusive, I am enabled to use many of the parts aforedescribed without any change whatsoever, whereas certain other of the parts aforedescribed may be utilized by slightly modifying the form or construction thereof. Thus the actuated cam plate and the resilient metal member 49 (Fig. 22) are identical with the corresponding parts aforedescribed and perform like functions. The insulating plate 68 is essentially like the plate 68 aforedescribed, except that only the two diametrically opposed peripheral notches 68 and 68 are provided. The bridging contactor 69 is similar to the contactor aioredescribed, except that only the two diametrically opposed arms 69, 69 and their associated parts are provided for assembly thereof in cooperative relationship to insulating plate 68. The actuating cam plate 63 differs from the corresponding cam plate 11- lustrated in Fig. 8 only in omitting the lug 63 with its bent end portion 63 ,-the latter being unnecessary and undesired for the reason that unlimited rotation of the actuating cam plate in either direction is contemplated for the switch of Figs. 20 to 24. The ratchet plate 31 differs from the corresponding part aforedescribed in providing, in addition to the radial lugs or projections 43 to 48, two additional radial lugs 88 and 8l,-the radial center lines of all of said lugs being spaced apart through arcs or angles of 45 degrees.

For the switch of Figs. 20 to 24 I provide a special form of molded insulating base 82 (Figs. 20 and 21) which is of symmetrical contour as shown. Base 82 is provided with six radial notches arranged in diametrically opposed groups of three each, and designated by the numerals 83, 84, 85 and 86, 81, 88. Said notches open to the periphery of base 82 and to the upper surface of the latter, and the opposed side walls of each notch are provided with grooves (such as indicated at 83, 83") which likewise open to the upper surface of said base. The lower surface of base 82 is provided with a circular recess 89 which is similar to the recess 33 (Fig. 6) except that the radially enlarged or segment-form bosses 98, 9|, etc., are equally spaced around the entire bottom wall of recess 89,--a similar complete circular group of projections 92, 93, etc., being provided for reception of and interlocking engagement with the ratchet-plate 31 of Fig. 22. The bosses 90, 9|, etc., are provided with projections 80*, 9|, etc., as shown in Figs. 20 and 24. Six combined contact and terminal units of the same character as those aforedescribed are utilized, and the various parts of the switch are assembled in the manner aforedescribed (see Fig. 24). The metal top plate 94 is of a shape corresponding to the contour or periphery of base 82, and a single relatively thick insulating plate 95 is interposed between the. top plate 94 and base 82. The externally threaded hollow metal bushing 58 (Fig. 24) may be identical with the part aforedescribed,--the reducedlower end portion 58 thereof being upset over the ratchetplate 31, as indicated at 58 Bushing 58 may be provided with a vertical groove (as aforedescribed) to accommodate the lug 94 and to definitely position an indicating plate (not shown) having a lug which is likewise engageable with said groove.

The parts of the switch of Figs. 20 to 24 are preferably so assembled as to provide for pcsitioning of the contactor 69 in either of its off positions (which are spaced'apart through an arc of 180 degrees) ,care being taken to see that the arrow 60 or similar indicator on knob 68 is cooperatively related to the indicating plate (not shown) to indicate off positioning of the switch mechanism. Between the two off positions on the indicating plate the latter is preferably provided with the legends I, 2 and 3, to indicate either the first, second and third speeds of the controlled motor (according to the particular scheme of wiring) or to indicate closure of one of three electric circuits to be controlled thereby. It is to be noted in connection with Figs. 20 to 24 that the contactor 69 may be moved in a step-by-step manner with a snap action from any rotary position thereof. This feature is of considerable importance in certain installations or uses of the switch. Another important feature of the switch shown in Figs. 20 to 24 is that a double-break or double-make of the controlled circuit is insured in each instance, thus insuring a relatively high current-controlling ca pacity of the switch. While I have illustrated a large number of different forms of switches embodying my invention,'it is manifest that various other changes will readily suggest themselves to those skilled in the art. Thus by employing a ratchet-plate 31 of sufliciently rigidform and by forming the bosses and projections on the bottom wall of circular recess 89 (Fig. 20) to correspond exactly with .the arrangement shown in Fig. 6, it will be apparent that the base 82 might be employed in constructing each and all of the forms of switches herein shown and described. Also it will be understood that any other suitable form of knob or handle may be substituted for the knob 60 shown herein. The various switches shown in Figs. 1 to 19, inclusive, have a standard rating of 5 amperes, volts, or 2 amperes, 250 volts; whereas the switch illus trated in Figs. 20 to 24 has a much higher current-carrying or current-controlling capacity.

What I claim as new and desire to secure by Letters Patent is:

1. In a rotary snap switch adapted for concealed mounting, in combination, an insulating base, a bushing rigidly attached to said base and projecting from the upper surface thereof, a spindle rotatably supported by said bushing, a bridging contactor rotatable in opposite directions about said spindle, means for effecting rotation of said contactor in either direction with a snap action from a given position thereof, said means comprising a cam plate rotatable with said spindle, a second cam plate rotatable with said contactor, a flat insulating plate to which said contactor and said second cam plate are rigidly attached in insulated relationship to each other, a lug associated with said second cam plate and resiliently biased upwardly toward said base, means comprising a plurality of pairs of shoulders associated with the lower surface of said base, said lug being normally positively engaged with the shoulders of any pair to restrain said contactor and said second cam plate against rotary movement pending release of said lug from said pair of shoulders as an incident to axial movement of said contactor and said second cam plate by said cam plate first mentioned, and a coiled compression spring interposed between the lower end portion of said spindle and said second cam plate, whereby upon release of said lug said second cam plate is biased by said spring to move with a snap action in a direction corresponding to the direction of movement of said cam plate first mentioned, said lug upon release thereof being adapted to positively engage the next succeeding pair of shoulders, whereby said second cam plate is restrained against additional rotary movement in either direction pending a predetermined degree of rotary movement of said cam plate first mentioned.

2. In a rotary snap switch adapted for concealed mounting, in combination, an insulating base, a metal bushing rigidly attached to said base and projecting from the upper surface thereof, a spindle rotatably supported by said bushing, a bridging contactor rotatable in opposite directions about said spindle, means for effecting rotation of said contactor in either direction with a snap action from a given position thereof, said means comprising a cam plate rotatable with said spindle, a second cam plate rotatable with said contactor, a fiat punched plate of insulation to which said contactor and said second cam plate are rigidly attached in insulated relationship to each other, a lug associated with said second cam plate and resiliently biased upwardly toward said base, means comprising a plurality of pairs of shoulders associated with the lower surface of said base, said lug being normally positively engaged with any one of said pairs of shoulders to restrain said contactor and said second cam plate against rotary movement pending release of said lug from said pair of shoulders as an incident to axial movement of said contactor and said second cam plate by said cam plate first mentioned, a coiled compression spring interposed between the lower end portion of said spindle and said second cam plate, whereby upon release of said lug said second cam plate is biased by said spring to move with a snap action in a direction corresponding to the direction of movement of said cam plate first mentioned, said lug upon release thereof being adapted to positively engage the next succeeding pair of shoulders, whereby said second cam plate is restrained against additional rotary movement pending a predetermined degree of rotary movement of said cam plate first mentioned, and a plurality of refiexed resilient stationary contacts secured to said base and into and out of engagement with which said contactor is adapted to move, the free end portions of said contacts being extended below said base in planes substantially parallel to the axis of said contactor to accommodate the axial movements of the latter as an incident to circuit commutating operation of the switch.

3. In an electric snap switch, in combination, an insulating base having an opening formed therein, a metal plate rigidly secured to the lower surface of said base and having an opening registering with said base opening, said metal plate having a multiplicity of projections formed integrally therewith and projecting radially therefrom to provide radial notches therebetween, a cam plate having a fiat circular portion adapted to seat against said metal plate and rotatable with respect thereto, said cam plate having a pair of downwardly converging double-inclined cams arranged at diametrically opposite ends of said fiat portion and offset downwardly from the plane of the latter, a second cam plate having a pair of downwardly converging double-inclined cams adapted for cooperation with the cams aforementioned, a flat plate of insulation to the upper surface of which said second cam plate is rigidly secured, a contactor rigidly secured to the lower surface of said insulating plate and having portions exposed about the periphery of the latter, a metal member also rigidly secured to the upper surface of said insulating plate, said metal member having a lug formed thereon and resiliently biased upwardly into the plane of said metal plate first mentioned when said cam plates are in the normal positions thereof respectively, a spindle penetrating all of said elements and having a driving connection with the cam plate first mentioned, means attached to said spindle adjacent to the upper end thereof to prevent axial displacement thereof in one direction, said spindle having a flange located adjacent to the lower end thereof, a coiled compression spring interposed between said flange and said second cam plate, whereby the latter is biased into engagement with the cam plate first mentioned, said first mentioned cam plate when rotated by said spindle being adapted to effect axial movement of said second cam plate to increase the degree of compression of said spring pending release of said lug from said notched plate, whereupon said second cam plate and the contactor and lug associated therewith are moved with a snap action in the direction of rotation of the spindle to a position wherein said lug engages the next succeeding notch in said 'metal plate, and a plurality of resilient stationary contacts adapted for cooperation with said contactor. said stationary contacts extending downwardly in the direction of the axis of said spindle to thereby accommodate the axial movement of said contactor as an incident to the axial movement of said second cam plate associated therewith.

4. In an electric snap switch of the rotary type adapted for concealed 'mounting, in combination, a molded insulating base having a substantially circular recess formed in the lower face thereof, said base having a passage formed therein and opening to said recess substantially centrally of the latter, said recess having a raised portion formed in the bottom wall thereof and surrounding said passage, a metal plate having an opening registering with said passage and adapted to seat against said raised portion, means including a shouldered bushing the lower end of which is upset to secure said plate rigidly and non-rotatably to said base, said metal plate having a plurality of radial notches formed therein, a cam plate having a fiat circular portion adapted to seat against said metal plate and rotatable with respect thereto, a second cam plate superimposed upon said first cam plate and adapted for cooperation therewith, said cam plates each having two pairs of downwardly converging double-inclined cam surfaces adapted to nest within each other in the normal positions thereof, an insulating plate of circular contour in fixed spaced relation to the upper surface of which said second cam plate is rigidly secured, a resilient metal member also rigidly secured to the upper surface of said insulating plate, said member having an integral lug penetrating said second cam plate and adapted for positive engagement with the walls of one of the notches in said first mentioned plate when said cam plates are in nested position, spring means for biasing said second cam plate into engagement with said first cam plate, means for effecting rotation of said first cam plate in either direction from a given position thereof, said first cam plate acting to move said second cam plate and said lug whereby the latter is released for rotary movement thereof into engagement with the walls of the next succeeding notch in said first mentioned plate, said spring cooperating with said cam surfaces to effect such movement of said parts with a snap action, a bridging contactor rigidly attached to the lower surface of said insulating plate, and having portions thereof exposed at spaced points about the periphery of said plate, a plurality of resilient stationary contacts located exteriorly of said recess and into and out of engagement with which said contactor is adapted to move, and cooperating means on said metal plate and said first mentioned cam plate to l mit the total range of angular movement of the latter.

5. In an electric snap switch of the rotary type, in combination, a molded insulatin base having subst lower far: is ned v.1

said plate aving a formed therein, a cam so lar per n adapted to l plate and being rotatable a second'cam plate superst cam plate and adapted .Jcr cooperation having we pairs of downwardly converging double-inclined earn surfaces adapted to nest within each other the normal positions thereof, plate of circular contour in fixed spaced relation to the upper surface of which said second plate is rigidly secured, a resilient metal member also rigidly secured to the upper surface of said insulating plate, said member having an integral lug penetrating said second earn plate and adapted for positive engagement with the walls of one of the notches in said first mentioned plate when said cam plates are in nested position, spring means for biasing said second cam plate into engagement with said first cam plate, means for effecting rotation of said first cam plate in either direction from a given position thereof, said first cam plate acting to move said second cam plate and said lug whereby the latter is released for rotary movement thereof into engagement with the walls of the next succeeding notch in said first mentioned plate, said spring cooperating with said cam surfaces to effect such movement of said parts with a snap action, a bridging contactor rigidly attached to the lower surface of said insulating plate and having portions thereof exposed at spaced points about the periphery of said plate,

cessed face of said base to accommodate the downward movement of said contactor as an incident to the operation of said cam surfaces.

6. In a snap switch of the rotary type, in combination, a molded insulating base havinga substantially circular recess formed therein and opening to the lower surface thereof, said base having a passage formed therein and opening to said recess substantially centrally of the latter, said base having a plurality of peripheral notches formed therein and arranged substantially rarially with respect to said passage, the opposed side walls of said notches having grooves formed theren and opening to the upper surface of said base, a plurality of combined resilient contact and wiring terminal members insertable into said notches from the last mentioned surface of said base, the wiring terminal portions of said members being adapted to seat downwardly into said grooves from the upper surface of said base to restrain said members against lateral displacement and endwise movement thereof in a downward direction, wiring terminal screws associated with the respective terminal portions, said base erewith, said plates each g formed to accommodate the shanks we and having shouldes engaged by the lat to positively restrain said against up T. displaceine t with respect said base, .esilient co tact portions members extending downwardly beyond the r wer s i of said base in planes at substantially right glee to said lower ur ace, and said notches formed to accord icciate said ea tions when lexed to as incident to engagement engagement therefrom of rotatable bridging ccntactor of suitable form.

7. In a snap switch the combination, a molded base having a. substantially circular recess formed therein and opening to the lower surface thereof, base having a passage formed therein and opening to said recess substantially central of the latter, said base having a plurality of peripheral notches formed therein and arranged substantially radial iv with respect to said passage, the opposed side walls of said notches having grooves formed therein and opening tothe upper surface of said base, a plurality of combined resilient contact and wiring terminal members insertable into said notches from the last mentioned surface of said base, the wiring terminal portions of said members being adapted to seat downwardly into said grooves from the upper surface of said base to restrain said members against lateral displacement and endwise movement thereof in a downward direction, wiring terminal screws associated with the respective terminal portions, said base being formed to accommodate the shanks of said screws and the heads of the latter being accessible from the exterior of said base, the resilient contact portions of said members extending downwardly beyond the lower surface of said base in planes at substantially right angles to said lower surface, said notches being formed to accommodate said resilient contact portions when flexed as an incident to movement of a rotatable bridging contactor of suitable form into and out of engagement therewith, and an insulating member rigidly secured to the upper surface of said base and adapted to overlie the exposed ends of said terminal portions, whereby said combined contact and wiring terminal members are restrained against endwise displacement in an upward direction.

8. In a snap switch of the rotary type, in combination, a molded insulating base having a substantially circular recess formed therein and opening to the lower surface thereof, said base having a passage formed therein and opening to said recess substantially centrally of the latter,

said base having a plurality of peripheral notches formed therein and arranged substantially radialiv with respect to said passage, the opposed side walls of said notches having grooves formed therein and opening to the upper surface of said base, a plurality of combined resilient contact and wiring terminal members insertable into said notches from the last mentlonedsurface of said base, the wiring terminal portions of said members being adapted to seat downwardly intosaid grooves from the upper surface of said base to restrain said portions against lateral displacement and endwise movement thereof in one direction, wiring terminal screws associated with the respective terminal portions, said base being formed to accommodate the shanks of said screws and the heads of the latter being accessible from the exterior of said base, the resilient contact portions of said members extending downwardly beyond said lower surface of said base in planes at substantially right angles to said surface, said notches being formed to accommodate said resilient contact portions when flexed as an incident to movement of a rotatable bridging contactor of suitable form into and out of engagement therewith, an insulating member rigidly secured to the upper surface of said base and adapted to overlie the exposed ends of said terminal portions, whereby said combined contact and wiring terminal members are restrained against upward displacement, said insulating member comprising a fiber plate, said plate having a number of integral lugs corresponding to the number of combined contact and wiring terminal members, and said lugs being bent downwardly over the heads of said wiring terminal screws to assist in properly insulating the latter.

9. In a rotary snap switch adapted for concealed mounting, in combination, a molded insulating base having a substantially circular recess formed therein and opening to the lower surfacethereof, said base having a passage extending therethrough and communicating with said recess substantially centrally of the latter, a metal member located within said recess and having an opening registering with said passage, said metal member having a plurality of peripheral notches formed therein, said base having a plurality of recesses formed therein and opening to the periphery thereof, a corresponding number of combined resilient contact and wiring terminal members freely insertable into said last mentioned recesses from the upper surface of said base to a position substantially flush with the latter, an insulating plate overlying the last mentioned surface of said base and said combined contact and terminal members, a metalplate overlying said insulating plate, a hollow metal bushing the reduced end portion of which is adapted to penetrate said plates, said base and said metal member and is upset over the latter to secure all of said parts in assembled relation, wiring terminal screws located within the respective peripheral recesses in said base and accessible from the exterior of the latter, the resilient contact portions of said members extending a substantial distance below the lower surface of said base, a metal cam plate adapted to rotatably seat against said metal member, a second metal cam plate adapted for cooperation with said cam plate first mentioned, a substantially circular insulating plate rigidly secured to said second cam plate in downwardly spaced relation to the lower surface of said base, said circular plate having a plurality of relatively shallow peripheral notches formed therein, a contactor carried by said circular plate and having bent end portions thereof seated within said notches last mentioned, the aforementioned resilient contact portions being normally'biased toward said circular plate in all positions of the latter, whereby the bent end portions of said contactor may be moved by said circular plate into and out of engagement with said resilient contact portions, a resilient metal member also carried by said circular plate, said last mentioned member having a lug penetrating said second cam plate to normally engage one or another of the notches in said first mention-ed metal member, a spindle adapted to bear within said bushing, said spindle having driving engagement with the cam plate first mentioned, a coiled compression spring interposed between the lower end of said spindle and the second cam plate, whereby kiwi,,itmistltwmtmw,.i,,,,,tilmtt,

upon rotation of said cam plate first mentioned said second cam plate and said lug are moved axially of said spindle against the bias of said spring, said lug when released from said metal member first mentioned being adapted to permit snap movement of said second cam plate into nesting engagement with the cam plate first men tioned, with corresponding movement of said circular plate and the contactor carried thereby, and said lug upon such movement thereof being adapted to positively engage the walls of the next succeeding notch in said first mentioned metal member.

10. In an electric snap switch of the rotary type adapted for concealed mounting, in combination, an insulating base having an opening formed therein, a metal member having an opening registering with said base opening, a hollow metal bushing having a reduced end penetrating said openings from the upper surface of said base and upset over said metal member to rigidly secure said parts in assembled relation, said metal member having a plurality of spaced slots formed therein and extending inwardly from the periphery thereof, a cam plate adapted to seat against said metal member and rotatable with respect thereto, said cam plate having 8. lug formed integrally therewith and adapted to move about a peripheral edge of said metal member, said peripheral edge having spaced shoulders formed thereon to positively limit movement of said cam plate in opposite directions respecnesting engagement with the cam plate first mentioned, a contactor associated with said sec ond cam plate and movable therewith, a resilient metal element also associated with said second cam plate and having a .lug penetrating the latter and adapted to positively engage the walls of one of the slots in said metal member in the nested position of said cam plates, a spindle adapted to bear within said bushing, said spindle having clearance from said second cam plate and having a driving connection with said cam plate first mentioned, a coiled compression spring interposed between the lower end portion of said spindle and said second cam plate to bias the latter toward said cam plate first mentioned, the latter being adapted upon a given degree of rotation of said spindle to raise said second cam plate and the lug associated therewith for release thereof, said lug when released being adapted to permit snap movement of said second cam plate and its associated contactor under the bias of said spring into nesting engagement with the cam plate first mentioned, whereupon said lug will positively engage the walls of the next succeeding slot in said metal member, and a plurality of resilient stationary contacts carried by said base and into and out of engagement with which said contactor is adapted to move, said contacts being sufiiciently long to accommodate the axial movement of said contactor below the lower surface of said base as an incident to the aforementioned raising of the cam plate associated therewith.

11. In a snap switch adapted for rotation in opposite directions, in combination, a relatively thin flat insulating member of substantially circular contour, said member having a substantially centrally located opening to provide sliding and rotating clearance for an actuating element of suitable form, said member having a plurality of relatively shallow substantially rectangular notches formed in the periphery thereof, a onetions of are eat at gles to the main the as being I ions of the uess thereof the respective notches whereby rlpherally spaced contactor e oded, said metal member having lugs med ltegrally with said bent end portions. and lugs being bent into engagement with the other face of said insulating member whereby the latter and said metal member are rigidly non-rotatably attached to each other.

ln a rotary snap switch. in combination a i'iat punched plate of insulating material of subtantially circular contour, said plate havin a substantially centrally located opening to provide slidin and rotating clearance for an actuating spindle of suitable form, said plate having a plurality of relatively shallow substantially rectangular notches formed in the periphery thereof. a bridging contactor comprising a one-piece sheet metal member extending across the lower face of said plate and having a relatively larger opening concentric with the aforementioned opening in said plate, said sheet metal member having a plurality of arms the radially extending end portions of which are bent at substantially right angles to the main body thereof. said end portions being adapted to seat within and having portions of the thickness thereof accommodated '"aces bv the respective notches whereby a plurality of peripherally spaced contactor surfaces are provided. said metal member having lugs formed integrally with said bent end portions, said lugs being bent into engagement with the upper face of said plate whereby the latter and said contactor are rigidly and non-rotatably secured to each other, said plate having a pair of diametrlcally alined openings formed therein on opposite sides of said central opening, a punched sheet metal cam member arranged upon the upper face of said plate. said cam member having-a pair of arms bent at substantially right angles thereto, said arms having reduced end portions which are insertable through said pair of openin s in said plate and bent over the lower face of the latter to rigidly secure said parts in assembled relation. said cam member having an opening of smaller size than said central plate opening to provide an abutment for a coiled compression spring. sa d cam member havlng'a pair of diametrically opposed segmental slots formed therein, and the opposed peripheral portions of said cam member defined by said slots being bent to provide two pairs of inclined cam surfaces which converge toward said upper face of the plate.

13. In a rotary snap switch, in combination, a relatively thin flat punched plate of insulating material of substantially circular contour, said plate having a substantially centrally located opening to provide sliding and rotating clearance for an actuating spindle of suitable form. said plate having a plurality of relatively shallow notches formed in the periphery thereof, a bridglng contactor comprising a one-piece sheet metal member extending across the lower face of said plate and having a relatively larger opening concentric with the aforementioned opening in said plate, said sheet metal member having a plurality of arms the end portions of which are bent at dated by the respective notch hereby a by of peripherally spaced co ctor surprovided, said metal 11? er having .0 med integrally with said end porsaid lugs being bent into engagem t with upper face of said plate whereby i -e latter and said contactor are and no ..-rotatably secured to each other, said plate having a pair of diametrically alined openings therein on. opposite sides of said central o ening, punched sheet metal cam member arranged upon the upper face of said plate, said cam member having a pair of arms bent substantially right angles thereto, saidarms having reduced end portions which are insertable through said pair of openings in said plate and bent over the lower face of the latter to rigidly secure said parts in assembled relation, said cam member having an opening of smaller size than said central plate opening to provide an abutment for a coiled compression spring, said cam member having a pair of diametrically opposed segmental slots formed therein, the opposed peripheral portions of said cam member defined by said slots being bent to provide two pairs of inclined cam surfaces which converge toward said upper face of the plate, said cam member having an additional opening formed therein adjacent to one of said arms, a resilient metal member interposed between said plate and said cam member and having at one end an integral angular lug extending outwardly through the last mentioned opening in said cam member, the other end of said metal member being formed to provide for clamping thereof between the upper face of said plate and the other arm of said cam member, and said metal member having formed therein an opening at least as large as and alined with the central opening in said plate.

14. In a snap switch adapted for attachment to a panel or similar support, in combination, a molded insulating base recessedfrom the lower surface thereof to accommodate the switch mechanism, said base being also formed to provide a plurality of recesses opening to the upper surface thereof, said last mentioned recesses having portions thereof opening to "the periphery of said base, a plurality of combined contact and wiring terminal members freely insertable into said last mentioned recesses from said upper surface to a position substantially flush with the latter, a metal top plate secured to said upper surface of said base and adapted to overl e the upper ends of said combined contact and wiring terminal members, a relatively thin plate of insulating material interposed between said top plate and the upper surface of said base, said insulating plate having a plurality of lugs formed integrally there-' with, terminal screws associated with said combined contact and wiring terminal members and accessible through the peripheral openings in said last mentioned base recesses, and said integral insulating lugs being bent downwardly over said terminal screws to assist in properly insulating the same.

15. In a snap switch adapted for attachment to a panel or similar support, in combination, a molded insulating base recessed from the lower surface thereof to accommodate the switch mech anism, said base being also formed to provide a plurality of recesses opening to the upper surface thereof, said last mentioned recesses having portions thereof opening to the periphery of said base, a plurality of combined contact and wiring terminal members freely insertable into said last mentioned recesses from said upper surface to a position substantially flush with the latter, a metal top plate secured to said upper surface of said base and adapted to overlie the upper ends of said combined contact and wiring terminal members, a relatively thin plate of insulating material interposed between said top plate and the upper surface of said base, said insulating plate having a plurality of lugs formed integrally therewith, terminal screws associated with said combined contact and wiring terminal members and accessible through the peripheral openings in said last mentioned base recesses, said integral insulating lugs being bent downwardly over said terminal screws to assist in properly insulating the same, and said integral insulating lugs being readily removable from said insulating plate by hand after complete assembly of the switch parts.

16. In a snap switch of the rotary type, in combination, a molded insulating base having a sub stantially circular recess formed therein and opening to the lower surface thereof, said base having a passage formed therein and opening to said recess substantially centrally of the la ter, said base having a plurality of peripheral notches formed therein and arranged substantially radially with respect to said passage, the opposed side walls of said notches having grooves formed therein and extending downwardly a pre determined distance from the upper surface of said base, a plurality of resilient contact members reflexed at the upper ends thereof respectively,

terminal members loosely positioned within the respective reflexed portions of said contact mem bers, terminal screws having threaded engagement with said terminal members, said contact and terminal members and screws when partially assembled being insertable as units downwardly from the upper surface of said base and seating within said grooved peripheral notches in a relation substantially flush with said upper surface, the free end portions of said contact members extending downwardly beyond the lower surface of said base and the same being bent to normallyextend inwardly beyond the peripheral wall of said first mentioned recess, said terminal screws being located within said notches whereby the same are accessible from the exterior of said base, a metal supporting plate overlying the upper surface of said base and the contact and terminal members associated with the latter, a fiber insulating plate interposed between said metal plate and said upper surface of the base, said plate having a plurality of lugs formed integrally therewith and initially extending outwardly in the plane thereof, and said lugs being bent downwardly over said terminal screws to assist in insulating the latter after attachment of wires thereto.

17. In a rotary snap switch, in combination, a molded insulating base having a substantially circular recess formed therein and opening to the lower surface thereof, said base having a passage extending therethrough and communicating with said recess substantially centrally of the latter, said base having a group of three peripheral notches formed therein at one side thereof, the radial center lines of said notches being spaced apart at angles of approximately forty-five degrees, said base having a fourth peripheral notch diametrically opposed to the middle notch of the group aforementioned, four sets of combined contact and terminal members insertable within the respective notches from the upper surface of said base to a position-substantially flush with said upper surface, an insulating plate overlying said upper surface of the base to retain said combined contact and terminal members in assembled relation, the contact portions of said members being resilient and the same extending downwardly a substantial distance beyond the lower surface of said base and the free ends thereof being normally biased inwardly beyond the periphery of said circular recess, a contactor-carrier comprising a relatively thin fiat insulating plate of substantially circular contour arranged in a plane substantially parallel to the lower surface of said base, the circumference of said plate being greater than the circumference of said recess and said plate being interposed between the resilient contact portions aforementioned to definitely tension the latter, a contactor carried by said plate, said contactor comprising a sheet metal member having a group of three arms the radial centers of which are spaced substantially forty-five degrees apart and a fourth arm diametrically 0pposed to the middle arm of the group aforementioned, each of said arms having an outer endportion bent at substantially a right angle with respect thereto to provide a contactor surface, said plate having peripheral notches to accommodate a part of the thickness of said bent end portions, said metal member having means associated therewith to provide for rigid and permanent attachment thereof to said plate, said contactor having an off position wherein said single contactorsurface is disengaged from all of the group of three resilient contact portions and all of said group of three contactor surfaces are disengaged from said single resilient contact portion, said contactor also having three on positions wherein said single contactor surface may be engaged in sequence with said group of three resilient contact portions while said group of three contactor surfaces are simultaneously engaged in sequence with said single resilient contact portion, and associated means for insuring movement of said contactor from each position thereof to another with a snap action.

18. In a rotary snap switch, in combination, a molded insulating base having a substantially circular recess formed therein and opening to the lower surface thereof, said base having a passage extending therethrough and communicating with said recess substantially centrally of the latter, said base having a group of three peripheral notches formed therein at one side thereof, the radial center lines of said notches being spaced apart at angles of approximately forty-five degrees, said base having a fourth peripheral notch diametrically opposed to the middle notch of the group aforementioned, four sets of combined contact and terminal members insertable within the respective notches from the upper surface of said base to a position substantially flush with said upper surface, an insulating plate overlying said upper surface of the base to retain said combined contact and terminal members in assembled relation, the contact portions of said members being resilient and the same extending downwardly a substantial distance beyond the lower surface of said base and the free ends thereof being normally biased inwardly beyond the periphery of said circular recess, a contactorcarrier comprising a relatively thin flat insulating plate of substantially circular contour arranged in a plane substantially parallel to the lower surface of said base, the circumference of said plate being greater than the circumference of said recess and said plate being interposed between the resilient contact portions aforementioned to definitely tension the latter, a contactor carried by said plate, said contactor comprising a sheet'metal member having a group of three arms the radial centers of which are spaced substantially forty-five degrees apart and a fourth arm diametrically opposed to the middle arm of the group aforementioned, each of said arms having an outer end portion bent at substantially a right angle with respect thereto to provide a contactor surface, said plate having peripheral notches to accommodate a part of the thickness of said bent end portions, said metal member having means associated therewith to provide for rigid and permanent attachment thereof to said plate, said contactor having an off position wherein said single contactor surface is disengaged from all of the group of three resilient contact portions and all of said group of three contactor surfaces are disengaged from said single resilient contact portion, said contactor also having three'on positions wherein said single contactor surface may be engaged in sequence with said group of three resilient contact portions while said group of three contactor surfaces are simultaneously engaged in sequence with said single resilient contact portion, and

- associated means for insuring movementof said notches formed therein at the opposite side thereof, the radial center lines of the notches of each group being spaced apart at angles of approximately forty-five degrees and'the radial center lines of the adjacent end notches of the respective-groups being spaced apart at angles of approximately ninety degrees, six sets of combined contact and terminal members insertable within the respective notches from the upper surface of said base to a position substantially flush with said upper surface, an insulating plate overlying said upper surface of the base to retain said combined contact and terminal members in assembled relation, the contact portions of'said members being resilient and the same extending downwardly a substantial distance beyond the lower surface of said base and the free ends thereof being normally biased radially inwardly toward the passage aforementioned, a

- contactor-carrier comprising a flat punched plate of insulating material of substantially circular contour arranged in parallel spaced relation to the lower surface of said base, said plate being of larger diameter than said recess and the same being arranged between the aforementioned groups of resilient contact portions to definitely tension the latter, said plate having a pair of diametrically opposed relatively shallow peripheral notches formed therein, a contactor rigidly and non-rotatably attached to said plate, said contactor comprising a sheet metal member having a pair of diametrically opposed arms the respective outer ends of which are bent at substantially right angles thereto to seat within and having a part of the thickness thereof accommodated by said notches in the plate, said contactor having two off positions spaced apartby an angle ofapproximately one hundred and eighty degrees, said contactor also havingthree on positions between said off positions, the same being movable in either direction from any one of said on or off positions, said contactor in each instance affording a double-make or double-break in the circuit or circuits controlled thereby, and associated means for insuring step by-step snap movement ofsaid contactor in either direction from any given position thereof.

20. In a rotary snap switch, the combination with an insulating base having a substantially central opening formed therein, of a plurality of stationary contacts carried by said base and extending below the lower surface of the latter, a spindle mounted for rotary movement within said base opening, a contactor rotatably mounted on said spindle and adapted for movement into and out of bridging engagement with said stationary contacts, a metal plate rigidly attached to the lower surface of said base and havcam plate associated with said contactor and adapted to cooperate with said cam plate first mentioned, a member associated with said second mentioned cam plate and having a lug resiliently biased into the plane of said notched plate when said cam plates are positioned in the nor mal planes thereof respectively, a coiled compression spring interposed between the lower end of said spindle and said contactor, whereby said cam plates are biased into engagement with each other, said spindle being adapted upon rotation thereof in either direction to effect corresponding rotation of said first mentioned cam plate to effect axial movement of said second mentioned cam plate and the lug associated therewith, whereby said lug is released for snap movement thereof by said cam plates in the direction of rotation of said spindle to the next succeeding notch in said metal plate first mentioned.

GEORGE J. MEUER. 

